tpm: Convert sandbox-focussed tests to C

tpm: Convert sandbox-focussed tests to C

Some of the Python tests are a pain because they don't reset the TPM
state before each test. Driver model tests do this, so convert the
tests to C.

This means that these tests won't run on real hardware, but we have
tests which do TPM init, so there is still enough coverage.

Rename and update the Python tpm_init test to use 'tpm autostart',
since this fully initializes the TPM and performs the self tests.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>